 /*******************************************************************************
  * Copyright (c) 2000, 2005 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.ui.externaltools.internal.model;


 import java.net.MalformedURLException ;
 import java.net.URL ;

 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IStatus;
 import org.eclipse.core.runtime.Status;
 import org.eclipse.jface.resource.ImageDescriptor;
 import org.eclipse.jface.resource.ImageRegistry;
 import org.eclipse.swt.widgets.Display;
 import org.eclipse.swt.widgets.Shell;
 import org.eclipse.ui.IWorkbenchPage;
 import org.eclipse.ui.IWorkbenchWindow;
 import org.eclipse.ui.plugin.AbstractUIPlugin;
 import org.osgi.framework.Bundle;
 import org.osgi.framework.BundleContext;

 /**
  * External tools plug-in class
  */
 public final class ExternalToolsPlugin extends AbstractUIPlugin {
     /**
      * Status representing no problems encountered during operation.
      */
     public static final IStatus OK_STATUS = new Status(IStatus.OK, IExternalToolConstants.PLUGIN_ID, 0, "", null); //$NON-NLS-1$

     private static ExternalToolsPlugin plugin;
     
     private static final String EMPTY_STRING= ""; //$NON-NLS-1$

     /**
      * Create an instance of the External Tools plug-in.
      */
     public ExternalToolsPlugin() {
         super();
         plugin = this;
     }

     /**
      * Returns the default instance of the receiver.
      * This represents the runtime plugin.
      */
     public static ExternalToolsPlugin getDefault() {
         return plugin;
     }

     /**
      * Returns a new <code>IStatus</code> for this plug-in
      */
     public static IStatus newErrorStatus(String message, Throwable exception) {
         if (message == null) {
             message= EMPTY_STRING;
         }
         return new Status(IStatus.ERROR, IExternalToolConstants.PLUGIN_ID, 0, message, exception);
     }

     /**
      * Returns a new <code>CoreException</code> for this plug-in
      */
     public static CoreException newError(String message, Throwable exception) {
         return new CoreException(new Status(IStatus.ERROR, IExternalToolConstants.PLUGIN_ID, 0, message, exception));
     }

     /**
      * Writes the message to the plug-in's log
      *
      * @param message the text to write to the log
      */
     public void log(String message, Throwable exception) {
         IStatus status = newErrorStatus(message, exception);
         getLog().log(status);
     }
     
     public void log(Throwable exception) {
         //this message is intentionally not internationalized, as an exception may
 // be due to the resource bundle itself
 getLog().log(newErrorStatus("Internal error logged from External Tools UI: ", exception)); //$NON-NLS-1$
 }

     /**
      * Returns the ImageDescriptor for the icon with the given path
      *
      * @return the ImageDescriptor object
      */
     public ImageDescriptor getImageDescriptor(String path) {
         try {
             Bundle bundle= getDefault().getBundle();
             URL installURL = bundle.getEntry("/"); //$NON-NLS-1$
 URL url = new URL (installURL, path);
             return ImageDescriptor.createFromURL(url);
         } catch (MalformedURLException e) {
             return null;
         }
     }

     /**
      * Returns the active workbench window or <code>null</code> if none
      */
     public static IWorkbenchWindow getActiveWorkbenchWindow() {
         return getDefault().getWorkbench().getActiveWorkbenchWindow();
     }
     
     /**
      * Returns the active workbench page or <code>null</code> if none.
      */
     public static IWorkbenchPage getActivePage() {
         IWorkbenchWindow window= getActiveWorkbenchWindow();
         if (window != null) {
             return window.getActivePage();
         }
         return null;
     }
     
     /**
      * Returns the active workbench shell or <code>null</code> if none.
      */
     public static Shell getActiveWorkbenchShell() {
         IWorkbenchWindow window = getActiveWorkbenchWindow();
         if (window != null) {
             return window.getShell();
         }
         return null;
     }

     /**
      * Returns the standard display to be used. The method first checks, if
      * the thread calling this method has an associated display. If so, this
      * display is returned. Otherwise the method returns the default display.
      */
     public static Display getStandardDisplay() {
         Display display = Display.getCurrent();
         if (display == null) {
             display = Display.getDefault();
         }
         return display;
     }

     /* (non-Javadoc)
      * @see org.eclipse.ui.plugin.AbstractUIPlugin#createImageRegistry()
      */
     protected ImageRegistry createImageRegistry() {
         return ExternalToolsImages.initializeImageRegistry();
     }

     /* (non-Javadoc)
      * @see org.osgi.framework.BundleActivator#stop(org.osgi.framework.BundleContext)
      */
     public void stop(BundleContext context) throws Exception {
         try {
             ExternalToolsImages.disposeImageDescriptorRegistry();
         } finally {
             super.stop(context);
         }
     }
 }

